The government has named companies that underpaid some staff the minimum wage.
The official list includes Northern Ireland businesses, horse racing trainers Alan King and Lucinda Russell, and retailer B&Q.
Those named will have to repay the money owed to employees.
Separately, new figures suggest that wages are trailing inflation.
That is a warning about household budgets.
Prices are increasing at a faster rate than earnings, leaving workers with lower real incomes.
The government list and the pay data demonstrate financial strain for workers.
Officials said further steps would follow for employers that underpaid workers.